If your Athlon box has a private RFC 1928 address like 192.168.x.x or 10.x.x.x.x then you can configure a private domain/zone for it. But you don't have to.
You also can edit /etc/myname and /etc/hosts to change to a not so confusing names.

If your box has a public IP then you should use the official name that goes with that IP address.

Now i have change:
/etc/myname
and
/etc/hosts
for use this domain:
athlon64.localdomain.it

But if i doing the command:
hostname
athlon64.domain_not_set.invalid
and also i haven't change /etc/resolv.conf
because if i change hostname and /etc/resolv.conf
i obtain this error when i tried to use program:
$ xfe
Xlib: connection to ":0.0" refused by server
Xlib: No protocol specified
while if i change only myname and hosts the problem isn't present.

Now how i can sure then when i restart the system all go well?
I have missed some files?

I sometimes use "shutdown now" to drop to single user mode then "exit" back up to try and reload/test some settings, i have noticed that PF still runs fine when doing this, am not sure about how many other "services" are running.

I use this on my main firewall as i also up the securelevel to 2 and cannot edit anything or reload much until i drop to single user mode which also drops my securelevel to 1.

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